From dc50eab76b709d68175a358d6e23a5a3890764d3 Mon Sep 17 00:00:00 2001 From: Daniel Baumann Date: Sat, 18 May 2024 19:39:57 +0200 Subject: Merging upstream version 6.7.7. Signed-off-by: Daniel Baumann --- fs/bcachefs/acl.c | 464 ++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 464 insertions(+) create mode 100644 fs/bcachefs/acl.c (limited to 'fs/bcachefs/acl.c') diff --git a/fs/bcachefs/acl.c b/fs/bcachefs/acl.c new file mode 100644 index 0000000000..3640f417cc --- /dev/null +++ b/fs/bcachefs/acl.c @@ -0,0 +1,464 @@ +// SPDX-License-Identifier: GPL-2.0 + +#include "bcachefs.h" + +#include "acl.h" +#include "xattr.h" + +#include + +static const char * const acl_types[] = { + [ACL_USER_OBJ] = "user_obj", + [ACL_USER] = "user", + [ACL_GROUP_OBJ] = "group_obj", + [ACL_GROUP] = "group", + [ACL_MASK] = "mask", + [ACL_OTHER] = "other", + NULL, +}; + +void bch2_acl_to_text(struct printbuf *out, const void *value, size_t size) +{ + const void *p, *end = value + size; + + if (!value || + size < sizeof(bch_acl_header) || + ((bch_acl_header *)value)->a_version != cpu_to_le32(BCH_ACL_VERSION)) + return; + + p = value + sizeof(bch_acl_header); + while (p < end) { + const bch_acl_entry *in = p; + unsigned tag = le16_to_cpu(in->e_tag); + + prt_str(out, acl_types[tag]); + + switch (tag) { + case ACL_USER_OBJ: + case ACL_GROUP_OBJ: + case ACL_MASK: + case ACL_OTHER: + p += sizeof(bch_acl_entry_short); + break; + case ACL_USER: + prt_printf(out, " uid %u", le32_to_cpu(in->e_id)); + p += sizeof(bch_acl_entry); + break; + case ACL_GROUP: + prt_printf(out, " gid %u", le32_to_cpu(in->e_id)); + p += sizeof(bch_acl_entry); + break; + } + + prt_printf(out, " %o", le16_to_cpu(in->e_perm)); + + if (p != end) + prt_char(out, ' '); + } +} + +#ifdef CONFIG_BCACHEFS_POSIX_ACL + +#include "fs.h" + +#include +#include +#include +#include + +static inline size_t bch2_acl_size(unsigned nr_short, unsigned nr_long) +{ + return sizeof(bch_acl_header) + + sizeof(bch_acl_entry_short) * nr_short + + sizeof(bch_acl_entry) * nr_long; +} + +static inline int acl_to_xattr_type(int type) +{ + switch (type) { + case ACL_TYPE_ACCESS: + return KEY_TYPE_XATTR_INDEX_POSIX_ACL_ACCESS; + case ACL_TYPE_DEFAULT: + return KEY_TYPE_XATTR_INDEX_POSIX_ACL_DEFAULT; + default: + BUG(); + } +} + +/* + * Convert from filesystem to in-memory representation. + */ +static struct posix_acl *bch2_acl_from_disk(struct btree_trans *trans, + const void *value, size_t size) +{ + const void *p, *end = value + size; + struct posix_acl *acl; + struct posix_acl_entry *out; + unsigned count = 0; + int ret; + + if (!value) + return NULL; + if (size < sizeof(bch_acl_header)) + goto invalid; + if (((bch_acl_header *)value)->a_version != + cpu_to_le32(BCH_ACL_VERSION)) + goto invalid; + + p = value + sizeof(bch_acl_header); + while (p < end) { + const bch_acl_entry *entry = p; + + if (p + sizeof(bch_acl_entry_short) > end) + goto invalid; + + switch (le16_to_cpu(entry->e_tag)) { + case ACL_USER_OBJ: + case ACL_GROUP_OBJ: + case ACL_MASK: + case ACL_OTHER: + p += sizeof(bch_acl_entry_short); + break; + case ACL_USER: + case ACL_GROUP: + p += sizeof(bch_acl_entry); + break; + default: + goto invalid; + } + + count++; + } + + if (p > end) + goto invalid; + + if (!count) + return NULL; + + acl = allocate_dropping_locks(trans, ret, + posix_acl_alloc(count, _gfp)); + if (!acl) + return ERR_PTR(-ENOMEM); + if (ret) { + kfree(acl); + return ERR_PTR(ret); + } + + out = acl->a_entries; + + p = value + sizeof(bch_acl_header); + while (p < end) { + const bch_acl_entry *in = p; + + out->e_tag = le16_to_cpu(in->e_tag); + out->e_perm = le16_to_cpu(in->e_perm); + + switch (out->e_tag) { + case ACL_USER_OBJ: + case ACL_GROUP_OBJ: + case ACL_MASK: + case ACL_OTHER: + p += sizeof(bch_acl_entry_short); + break; + case ACL_USER: + out->e_uid = make_kuid(&init_user_ns, + le32_to_cpu(in->e_id)); + p += sizeof(bch_acl_entry); + break; + case ACL_GROUP: + out->e_gid = make_kgid(&init_user_ns, + le32_to_cpu(in->e_id)); + p += sizeof(bch_acl_entry); + break; + } + + out++; + } + + BUG_ON(out != acl->a_entries + acl->a_count); + + return acl; +invalid: + pr_err("invalid acl entry"); + return ERR_PTR(-EINVAL); +} + +#define acl_for_each_entry(acl, acl_e) \ + for (acl_e = acl->a_entries; \ + acl_e < acl->a_entries + acl->a_count; \ + acl_e++) + +/* + * Convert from in-memory to filesystem representation. + */ +static struct bkey_i_xattr * +bch2_acl_to_xattr(struct btree_trans *trans, + const struct posix_acl *acl, + int type) +{ + struct bkey_i_xattr *xattr; + bch_acl_header *acl_header; + const struct posix_acl_entry *acl_e; + void *outptr; + unsigned nr_short = 0, nr_long = 0, acl_len, u64s; + + acl_for_each_entry(acl, acl_e) { + switch (acl_e->e_tag) { + case ACL_USER: + case ACL_GROUP: + nr_long++; + break; + case ACL_USER_OBJ: + case ACL_GROUP_OBJ: + case ACL_MASK: + case ACL_OTHER: + nr_short++; + break; + default: + return ERR_PTR(-EINVAL); + } + } + + acl_len = bch2_acl_size(nr_short, nr_long); + u64s = BKEY_U64s + xattr_val_u64s(0, acl_len); + + if (u64s > U8_MAX) + return ERR_PTR(-E2BIG); + + xattr = bch2_trans_kmalloc(trans, u64s * sizeof(u64)); + if (IS_ERR(xattr)) + return xattr; + + bkey_xattr_init(&xattr->k_i); + xattr->k.u64s = u64s; + xattr->v.x_type = acl_to_xattr_type(type); + xattr->v.x_name_len = 0; + xattr->v.x_val_len = cpu_to_le16(acl_len); + + acl_header = xattr_val(&xattr->v); + acl_header->a_version = cpu_to_le32(BCH_ACL_VERSION); + + outptr = (void *) acl_header + sizeof(*acl_header); + + acl_for_each_entry(acl, acl_e) { + bch_acl_entry *entry = outptr; + + entry->e_tag = cpu_to_le16(acl_e->e_tag); + entry->e_perm = cpu_to_le16(acl_e->e_perm); + switch (acl_e->e_tag) { + case ACL_USER: + entry->e_id = cpu_to_le32( + from_kuid(&init_user_ns, acl_e->e_uid)); + outptr += sizeof(bch_acl_entry); + break; + case ACL_GROUP: + entry->e_id = cpu_to_le32( + from_kgid(&init_user_ns, acl_e->e_gid)); + outptr += sizeof(bch_acl_entry); + break; + + case ACL_USER_OBJ: + case ACL_GROUP_OBJ: + case ACL_MASK: + case ACL_OTHER: + outptr += sizeof(bch_acl_entry_short); + break; + } + } + + BUG_ON(outptr != xattr_val(&xattr->v) + acl_len); + + return xattr; +} + +struct posix_acl *bch2_get_acl(struct mnt_idmap *idmap, + struct dentry *dentry, int type) +{ + struct bch_inode_info *inode = to_bch_ei(dentry->d_inode); + struct bch_fs *c = inode->v.i_sb->s_fs_info; + struct bch_hash_info hash = bch2_hash_info_init(c, &inode->ei_inode); + struct xattr_search_key search = X_SEARCH(acl_to_xattr_type(type), "", 0); + struct btree_trans *trans = bch2_trans_get(c); + struct btree_iter iter = { NULL }; + struct bkey_s_c_xattr xattr; + struct posix_acl *acl = NULL; + struct bkey_s_c k; + int ret; +retry: + bch2_trans_begin(trans); + + ret = bch2_hash_lookup(trans, &iter, bch2_xattr_hash_desc, + &hash, inode_inum(inode), &search, 0); + if (ret) { + if (!bch2_err_matches(ret, ENOENT)) + acl = ERR_PTR(ret); + goto out; + } + + k = bch2_btree_iter_peek_slot(&iter); + ret = bkey_err(k); + if (ret) { + acl = ERR_PTR(ret); + goto out; + } + + xattr = bkey_s_c_to_xattr(k); + acl = bch2_acl_from_disk(trans, xattr_val(xattr.v), + le16_to_cpu(xattr.v->x_val_len)); + + if (!IS_ERR(acl)) + set_cached_acl(&inode->v, type, acl); +out: + if (bch2_err_matches(PTR_ERR_OR_ZERO(acl), BCH_ERR_transaction_restart)) + goto retry; + + bch2_trans_iter_exit(trans, &iter); + bch2_trans_put(trans); + return acl; +} + +int bch2_set_acl_trans(struct btree_trans *trans, subvol_inum inum, + struct bch_inode_unpacked *inode_u, + struct posix_acl *acl, int type) +{ + struct bch_hash_info hash_info = bch2_hash_info_init(trans->c, inode_u); + int ret; + + if (type == ACL_TYPE_DEFAULT && + !S_ISDIR(inode_u->bi_mode)) + return acl ? -EACCES : 0; + + if (acl) { + struct bkey_i_xattr *xattr = + bch2_acl_to_xattr(trans, acl, type); + if (IS_ERR(xattr)) + return PTR_ERR(xattr); + + ret = bch2_hash_set(trans, bch2_xattr_hash_desc, &hash_info, + inum, &xattr->k_i, 0); + } else { + struct xattr_search_key search = + X_SEARCH(acl_to_xattr_type(type), "", 0); + + ret = bch2_hash_delete(trans, bch2_xattr_hash_desc, &hash_info, + inum, &search); + } + + return bch2_err_matches(ret, ENOENT) ? 0 : ret; +} + +int bch2_set_acl(struct mnt_idmap *idmap, + struct dentry *dentry, + struct posix_acl *_acl, int type) +{ + struct bch_inode_info *inode = to_bch_ei(dentry->d_inode); + struct bch_fs *c = inode->v.i_sb->s_fs_info; + struct btree_trans *trans = bch2_trans_get(c); + struct btree_iter inode_iter = { NULL }; + struct bch_inode_unpacked inode_u; + struct posix_acl *acl; + umode_t mode; + int ret; + + mutex_lock(&inode->ei_update_lock); +retry: + bch2_trans_begin(trans); + acl = _acl; + + ret = bch2_subvol_is_ro_trans(trans, inode->ei_subvol) ?: + bch2_inode_peek(trans, &inode_iter, &inode_u, inode_inum(inode), + BTREE_ITER_INTENT); + if (ret) + goto btree_err; + + mode = inode_u.bi_mode; + + if (type == ACL_TYPE_ACCESS) { + ret = posix_acl_update_mode(idmap, &inode->v, &mode, &acl); + if (ret) + goto btree_err; + } + + ret = bch2_set_acl_trans(trans, inode_inum(inode), &inode_u, acl, type); + if (ret) + goto btree_err; + + inode_u.bi_ctime = bch2_current_time(c); + inode_u.bi_mode = mode; + + ret = bch2_inode_write(trans, &inode_iter, &inode_u) ?: + bch2_trans_commit(trans, NULL, NULL, 0); +btree_err: + bch2_trans_iter_exit(trans, &inode_iter); + + if (bch2_err_matches(ret, BCH_ERR_transaction_restart)) + goto retry; + if (unlikely(ret)) + goto err; + + bch2_inode_update_after_write(trans, inode, &inode_u, + ATTR_CTIME|ATTR_MODE); + + set_cached_acl(&inode->v, type, acl); +err: + mutex_unlock(&inode->ei_update_lock); + bch2_trans_put(trans); + + return ret; +} + +int bch2_acl_chmod(struct btree_trans *trans, subvol_inum inum, + struct bch_inode_unpacked *inode, + umode_t mode, + struct posix_acl **new_acl) +{ + struct bch_hash_info hash_info = bch2_hash_info_init(trans->c, inode); + struct xattr_search_key search = X_SEARCH(KEY_TYPE_XATTR_INDEX_POSIX_ACL_ACCESS, "", 0); + struct btree_iter iter; + struct bkey_s_c_xattr xattr; + struct bkey_i_xattr *new; + struct posix_acl *acl = NULL; + struct bkey_s_c k; + int ret; + + ret = bch2_hash_lookup(trans, &iter, bch2_xattr_hash_desc, + &hash_info, inum, &search, BTREE_ITER_INTENT); + if (ret) + return bch2_err_matches(ret, ENOENT) ? 0 : ret; + + k = bch2_btree_iter_peek_slot(&iter); + ret = bkey_err(k); + if (ret) + goto err; + xattr = bkey_s_c_to_xattr(k); + + acl = bch2_acl_from_disk(trans, xattr_val(xattr.v), + le16_to_cpu(xattr.v->x_val_len)); + ret = PTR_ERR_OR_ZERO(acl); + if (IS_ERR_OR_NULL(acl)) + goto err; + + ret = allocate_dropping_locks_errcode(trans, + __posix_acl_chmod(&acl, _gfp, mode)); + if (ret) + goto err; + + new = bch2_acl_to_xattr(trans, acl, ACL_TYPE_ACCESS); + if (IS_ERR(new)) { + ret = PTR_ERR(new); + goto err; + } + + new->k.p = iter.pos; + ret = bch2_trans_update(trans, &iter, &new->k_i, 0); + *new_acl = acl; + acl = NULL; +err: + bch2_trans_iter_exit(trans, &iter); + if (!IS_ERR_OR_NULL(acl)) + kfree(acl); + return ret; +} + +#endif /* CONFIG_BCACHEFS_POSIX_ACL */ -- cgit v1.2.3